Pakistani security forces backed by helicopter gunships have killed at least 23 tribal militants in Balochistan province, officials say.
Tribesman say they are fighting for greater economic rights
Another 12 rebels were wounded in Dera Bugti district and 50 surrendered, officials said. A rebel spokesman told the BBC he knew nothing of the clash.
Last week, the authorities said they had killed about 30 rebels in the same area - claims the tribesmen denied.
Tribal militants want more control of the poor but gas-rich province.
Military operations had been going on in the Sangseela and Bhambhor Top areas of Dera Bugti district for four days, Balochistan government spokesman Raziq Bugti told the BBC.
He said security forces had intercepted Bugti rebel communications and found that 23 people had been killed.
It was unclear whether the security forces had actually seen the bodies of the tribesmen said to have been killed in the fighting.
Dera Bugti district official Abdul Samad Lasi, however, told the BBC that bodies of the dead were still at the scene and locals were preparing to bury them.
He said the injured had been taken to hospital.
The tribesman have said nothing about the reported clash, which took place in an area where it is virtually impossible to independently verify the two sides' competing accounts.
When contacted by the BBC, Agha Shahid Bugti of the Jamhoori Watan Party - a close relative of tribal leader Nawab Akbar Bugti - expressed ignorance about the latest incident.
When the authorities said last week that 31 Bugti rebels had been killed, the tribesmen vigorously rejected the official version.
They made the counter-claim that more than 35 security force personnel had been killed and at least three helicopters damaged - claims in turn denied by the authorities.
Security forces stepped up their crackdown on the militants following a failed assassination attempt on President Pervez Musharraf during a visit to the province in December.
Rebel tribesmen have been accused of attacking officials and government buildings as well as blowing up gas pipelines in the province, Pakistan's biggest and poorest.
The government is pumping millions of dollars into Balochistan with the aim of turning it into a regional economic and energy hub.
It has also been building military garrisons to secure the investments, which officials say will bring development to the people.
But many Baloch resent the growing presence of the armed forces - seen as imposing Islamabad's agenda - and support for the tribal rebels is growing, correspondents say.